Extjs ComboBox 动态选中第一项

   var storeinfo = Ext.create(‘Ext.data.Store‘, {
        model: SaleInfo,
        autoLoad: false,
        pageSize: 10000,

        proxy: {
            type: ‘ajax‘,
            url: ‘/URL/JSON‘,
            reader: {
                type: ‘json‘,
                rootProperty: ‘Data‘,
                totalProperty: ‘TotalCount‘
            }
        }
    });

    ////数据加载之后，回调设置ComboBox选择第一项
    storeinfo.load({
        scope: this,
        callback: function (records, operation, success) {
            if (records.length > 0) {
                Ext.getCmp("BranchId").select(storeinfo.getAt(0));
            }
            else {
                Ext.getCmp("BranchId").setRawValue("暂无独立法人");
            }
        }
    });